Continuous casting apparatus



United States Patent Inventor John B. Kelly Glenmoore, Pennsylvania Appl. No. 716,121

Filed March 26, 1968 Patented Oct. 20, 1970 Assignee By mesne assignment to Gulf 8:

Western Industrial Products Company Grand Rapids, Michigan a corporation of Delaware.

CONTINUOUS CASTING APPARATUS 3 Claims, 11 Drawing Figs.

US. Cl 164/275 822d 11/00 Field ofSearch 164/86, 54,

[56] References Cited UNITED STATES PATENTS 1,037,250 9/1912 Hinman 164/78 2,334,929 11/1943 Hone 164/78 Primary Examiner.l. Spencer Overholser Assistant Examiner V. K. Rising AtmrneyMeyer, Tilberry and Body ABSTRACT: Apparatus for periodically inserting divider members into the molten metal in the mold of a continuous casting machine to produce a cast strand comprising a plurality of individual sections joined by the divider members and narrow necks of solidified metal. The apparatus comprises means for maintaining a head of divider elements adjacent the mold and power means operable at predetermined intervals for inserting the elements into the molten metal in the mold.

CONTINUOUS CASTING APPARATUS The present invention is directed toward the continuous casting art and, more particularly, to apparatus for casting separator or divider elements at longitudinally spaced loca- 'tions in a continuous cast metal strand.

As is well known, during the continuous casting of metal, the continuously cast strand must subsequently be severed into lengths convenient for handling, storing, and further processing. Normally, in the past, the strand has been severed by the use of gas torches. or mechanical or hydraulic shears. These methods of severing the strand usually require relatively heavy and complex machines. Additionally, especially when cutting the larger size strands, the cutting operation can :be time consuming andexpensivc.

The present invention provides apparatus for casting separator or divider elements into a continuously cast strand of metal so that the cross-sectional area of metal which must subsequently be severed to reduce the strand to the desired lengths is greatly reduced.- 9

In accordance with one aspect of the present invention there is provided an apparatus for producing an elongated metal strand by continuously supplying molten metal to the upper end of a cooled, open ended mold of a desired crosssectional configuration while, simultaneously, withdrawinga continuous strand of metal from the lower end of'the mold at a rate commensurate with the rate of solidification taking place therein. The improvement to the apparatus includes means providing a head of relatively thin divider members formed from a materialwhich is substantially unaffected-by saidmolten metal, and each having across-sectional area perpendicular to-their thickness which is less than the cross-sectional area of the mold and adapted to be received therein; and,-power means for periodically inserting at least'one of :the .divider members into the molten metal in the mold so as to lie generally transversely in the mold whereby the resultant continuousstrand'of metal comprises a-plurality of metal-sections separated'by'the members and joinedby aportion of solidified metal determined bythe differencein the cross sectional area of the=members and the mold.

In accordance with another aspect of the'invention there is provided an improvement'to a'continuous casting machine'of the type including a-.cooled,openended mold, first means for supplying molten:metal to the .upper end of the mold, and second means'for withdrawingsolidified-metal from' the lower end ofthe mold. The improvement comprises means for maintaininga'headof divider member adjacent the mold periodically placing one of the divider members into the moltenmetal in said mold in aposition whereinit extends generally'transversely of the mold.

Accordingly, a primary object of the present invention is the provision of apparatus for providing transversely extendingdividerplates at longitudinally spaced locations in a continu ously cast metal strand.

Yetianother object is the provision of apparatus for forming a continuously cast metal strand in a manner which greatly facilitatessubsequent-severing of the stranditothe desired length.

Still a further object'of the present invention isthe provision of apparatus for inserting divider plates'intothe'mold of a continuous 'casting machine so that'the divider plates'are integrallycast inJthe cast metal strand.

These and other objects and advantages will become apparent from the" following description when read in conjunction with the accompanying drawing wherein:

FIG. .1 is a side elevation,.somewhat diagrammatic, of a. continuous casting machine incorporating onetype of apparatus FIG. 6 is a side elevational view, partially in section. of a continuously cast strand having a modified form of divider member cast therein;

FIG. 7 is a cross-sectional view taken on line 7-7 of FIG. 6; l

FIG. 8 is a side elevational view, partially in cross section, of a cast metal strand of the type shown in FIG. 6 immediately after it has been severed;

FIG. 9 is a plan view of a third form of divider member which can be utilized in the practice of the subject invention;

and,

FIG. 10 is an end view of the dividermember shown in FIG.

Referring now to the drawings wherein the showings are for the purpose of illustrating preferred embodiments of the in:

vention only, and not for the purpose of limiting same,FlG 1. v

-ish 10 in any convenient manner such as,'for example,'by the use of a conventional pour ladle 14. The tundish is provided with an outlet nozzle 16 through which the molten metal passes to the open upper end 18 of the mold 12. As is usual practice, the lower end 20 of the mold I2 is, during start-up, closed by the upper end of a starter bar which is slowly withdrawn as the molten metal solidifies within the mold. As the starter bar is withdrawn the solidified strand is continuously withdrawn from the mold as additional molten metal is supplied thereto and a substantially uniform level of metal maintained in the mold. The rate of withdrawal of the strand 22 from the mold is controlled by withdrawal rolls 24 which are positioned a substantial distance beneath the outlet of the mold.

The strand 22 is continuously withdrawn from the mold in onecontinuous piece and, at some subjacent location, is normallysevered into billets or slabs having a size convenient for .handling and further working such as rolling. As previously discussed, in thepast, this severing has been accomplished by gas torchesor large mechanical or hydraulic shears As can be strand of a predetermined length joined by the divider plates and a small neck or section of metal. Preferably, the divider plates are inserted directly into the molten metal within the .mold at predetermined intervals so that strand sections intermediate the dividers are of a desired, predetermined length.

' Althoughthe dividers could have a variety of configurations,

theyare desirably formed so as tobe relatively thin and have an outer periphery which closely approximates the cross-sectional opening of the mold, but is only slightly smaller. Additionally, for reasons which will hereafter become apparent, it

is-important that the divider plates have an open portion extending through their thickness dimension and located approximately centrally relative to the outer periphery. The divider plates could be formed from substantially any material capable of maintaining its structural integrity when subjected to temperatures in the range of the molten metal; however, according to the preferred embodiment, these divider plates are desirably formed from thin sheets of asbestos or a high temperature resistant ceramic.

Referring specifically to FIGS. 3, 7 and 9 there are shown three of the many possible divider configurations which could be utilized in practice of the subject invention. The three configurations shown are all of a rectangular outer cross section as determined by the cross-sectional shape of the mold opening. Preferably, if the mold opening were other than rectangular as, for example, eliptical, the dividers would have an outer peripheral shape substantially the same as the mold but of a slightly smaller size.

Referring specifically to FIG. 1, it is seen that a stack 30 of divider members 32 of the type shown in FIG. 3 are positioned subjacent the outlet of the tundish with their central openings 34 aligned with the outlet of the mold so this permits the molten metal 36 to flow vertically downwardly therethrough into the open upper end of the mold 12. As best shown in FIG. la, the divider members 32 are maintained in aligned, stacked relationship by a guide frame formed from four angle irons 38. The divider members are maintained in the angle iron guides and periodically dropped one at a time by a discharge mechanism which includes a pair of arm members 40 and 42 which are actuated by oscillating mechanisms 44 and 46, respectively. As shown, arm 40 includes a thin, transversely extending, end portion which is arranged to enter between the bottom two divider members and the stack 30. The arm member 42 includes a generally similarly arranged portion 50 which extends beneath the bottom divider member in the-stack.

' When members 40 and 42 are in the positions shown on FIG. 1, the divider members will be maintained within the guide frame; however, when member 42 is oscillated from beneath the stack the bottom divider member will be released and fall into the open upper end of themold. Member 42 is .then oscillated to bring portion 50 back under the guide frame and member 40 is then oscillated to remove its horizontally extending portion from beneath the remaining divider members in the guide frame. The remaining divider members then drop and the lower member comes into engagement with the top surface of portion 50 of member 42. Subsequent oscillation of member 40 then moves its arm portion back into position between the bottom and second divider member on the stack.

Because of the high specific gravity of high molten metals, the divider member which has been dropped into the open upper end of the mold will normally float onthe top of the molten metal therein. However, since the molten metal is continuously solidifying in a thin outer shell adjacent the inner walls of the mold, the outer edge of the divider member engages this solidifies metal and is bonded thereto. The continued downward movement of the strand 22 under the influence of the withdrawal rolls 24 pulls the divider member along through the mold and additional molten metal is deposited on its upper surface.

As the strand moves downwardly from the mold, the metal solidifies about the divider member and effectively bonds thereto. As is usual, the strand has not completely solidified throughout its cross section until it is moved a substantial distance below the open end of the mold. As shown in FIG. 1, a molten core 54 usually extends a substantial distance down into the cast strand. Since the metal undergoes contraction when it solidifies, an opening must extend centrally through the thickness dimension of the divider members 32. This opening permits additional molten metal to flow through the divider member into the space created by the solidification and contraction of the molten metal beneath the divider.

As is apparent, the spacing of the sections 32 in the strand 22 are dependent upon the rate of withdrawal of the strand from the mold and the time interval between insertion of the successive dividers. Obviously, any particular type of control arrangement could be provided for providing the proper spacing of the sections. For example, a simple counter mechanism actuated by the withdrawal rolls could be used to control the inserting mechanism.

Although the preferred divider member structure and insertion apparatus is as described in FIGS. 1 and 3, obviously, various other types of divider member configurations could be used and the dividers insertedeither manually or by substantially different apparatus. -One different type of apparatus which could be utilized for inserting dividers of the type shown in FIG. 7, is shown in FIG. 5. Asshown in FIG. 5 a plurality of the divider members 58 are positioned in stacked relationship adjacent the open upper end of the mold. Dividers 58 have an opening which extends inwardly from one side thereof. Ac-

cordingly with the opening 60 aligned with the stream of mo lten meta exiting from the tundish, the divider can be slid horizontally into alignment with the open end of the mold to then drop vertically into themold opening. In the FIG. 5 embodiment, divider members 58 are maintained in stacked relationship by a guide box 60. Box;6l has openings 62 formed in opposite sidewalls. The openings 62 are of a height just sufficient to allow one of the divider members "to be slid therethrough. The means for sliding the dividermembersoutwardly through the opening 62 could be of a variety of types; however, they preferably comprise a fluid cylinder 64 having its piston rod 66 provided with a plunger which engages the right hand edge of the lowermost divider member 58. Accordingly, reciprocation of the piston rod causes the lowermost divider member to be moved from its position at the bottom of the stack and into alignment with the open upper end of the mold. I

Altemately, the divider members could, for example, be of the type shown in FIG. 9. As shown therein, the divider member 70 is formed in two sections 72 and 74 which are arranged to be interconnected by a tongue and groove connection arrangement 76. For reasons previously discussed, the sections 72 and 74 each include an opening 78 and 80, which cooperate to form a central opening through the resulting divider member 70. This particular form of divider member could be assembled prior to being aligned with the mold and inserted with an apparatus such as shown in FIG. 5. Preferably, however, the sections 72 and 74 would be positioned on opposite sides of the mold and simultaneously actuated inwardly into engagement.

The invention has been described in great detail sufficient to enable one of ordinary skill in the continuous casting art to make and use the same. Obviously, modifications and alterations of the preferred embodiments of the invention will occur to others upon a reading and understanding of the specification and it is my intention to include all such modifications and alterations insofar as they come within the scope of the appended claims.

Iclaim:

1. In a continuous casting machine including a cooled, open ended mold, first means for supplying molten metal to the upper end of the mold, and second means for withdrawing the solidified metal from the lower end of the mold, the improvement comprising: head maintaining means for maintaining a head of divider members adjacent the mold; and, power means for periodically placing divider members into the molten metal in said mold in a position wherein they extend generally transversely of the mold.

2. The improvement as defined in claim 1 wherein said divider members each have a central opening and said head maintaining means supports said members with their openings in alignment and above said mold.

3. The improvement as defined in claim 2 wherein said head maintaining means maintains said divider members in vertical alignment with said mold. 

